Improvement in piano-locks



THIELEMANN 8v MEYER.

. Piano Look. No. 103,525. Patented May 24, 1870.

waited 53mins iijatrnt Gtjifliu.

JOHN THIELEMANN AND PHILIPP MEYER, OF NEWARK, NEW JERSEY I ASSIGNORS TO WILLIAM SELLERS.

Letters Patent No. 103,525, dated May 24, 1870.

IMPROVEMENT IN PIANO-LOCKS.

The Schedule referred to in. these Letters Patent and making; part of the same.

To all whom it may concern:

Be it known that we, J OHN THIELEMANN and PHILIPP MEYER, both of Newark, in the county of Essex and State of New Jersey, have invented a new and improved Lock for Piano-Fortes, 850.; and we do hereby declare the following'to be a full, clear, and exact description thereof, which will enable those skilled in the art to make and use the same, reference being had to theaccompanying drawing forming part of this specification, in which drawing- Figure 1 represents a sectional face view of this invention when the lock is unlocked.

Figure 2 is a similar view of the same when locked.

Figure 3 is a transverse vertical section of the same.

Figure 4 is a plan or top view of the-same.

Similar letters indicate corresponding parts.

This invention consists in the arrangement of two segmental gears, one of which is acted on by the 'key' and tumbler or detaining spring, while the other carries a segmental bolt, in such a manner that, by turning the key segment, a revolving motion is imparted to the bolt segmenaand the bolt is thrown in or out, and when the bolt is turned in,'the slot in the faceplate of the lock is completely filled up, thereby improving the appearance of the lock, and preventing dust and dirt from getting in and disturbing the correct operation of the lock.

In the drawing, the letterA designates the case, which incloses the locking mechanism, and which is attached to the face-plate B. Y

The locking mechanism consists chiefly of two segmental gears, O D, which revolve on their centers, and one of which is provided with a square hole, a, to admit the key.

A spring, I), which acts on a projection, c, of the segment C, serves to detain the same in either ot' its extreme positions, thus taking the place of the tumblers in an ordinary lock.

The segment D carries the segmental bolt E, which is provided with a head,,c, and, if said segment is turned to the position shown in fig. 2, the bolt E- i; thrown out and made to catch in the locking-plate l both the face-plate of the lock and-the locking-plate being provided with a slot, f, corresponding to the sect-ion of the bolt, (see fig.4.) As the head of the bolt catches over the edges of the narrow portion of the slot in the looking-plate, the lock is fastened. When the segments 0 D areturned back to the position shown in fig. 1, the bolt E completely fills up the slot in the face-plate, being prevented from turning down any further than desired by the edge of the segment D coming in contact with the inner surface of the face-plate.

By these means the appearance of the lock is materially improved, and all dirt and dust are excluded; and, furthermore, by the action of the spring I), the two segments 0 D are firmly retained in position and all jingling noise of the lock is avoided.

\Vhat we claimas new, and desire to secure by Letters Patent, is

The toothed segments 0 D, the latter formed directly upon the bolt, and spring I), in combination with the bolt E, the latter entirely filling the perforation f when unlocked, as and for the -purpose set forth.

JOHN THIELEMANN. PHILIP]? MEYER. Witnesses:

JOHN WERNER, I'InnRY ACKERMANN. 

